“But if the bondsman shall say, “I love my master, my wife and my children- I shall not go free;” then his master shall bring him to the court and shall bring him to the door or to the doorpost, and his master shall bore through his ear with the awl, and he shall serve him forever.” (Ex. 21:5-6)

The Jew is commanded to ascend via humility and lowliness and to break down his own egotism. He is obligated to liberate himself from his enslavement to himself and to be a free man vis-a-vis everyone but G-d. To be a slave to mortal man or to oneself is a profound sin. If the slave of a Jew does not wish to go free [after six years], his ear is pierced with an awl, and our sages explain (Kiddushin 22b):

How is the ear different from all other parts of the body? G-d said, “If one's ear heard Me say on Mount Sinai (Lev. 25:55), 'The Children of Israel are slaves to Me', slaves to Me, not slaves to slaves, and he still went and acquired a master for himself, that ear must be pierced.”
R. Shimon ben Rebbe's exposition on this verse was like a gem: How are the door and the doorpost different from all other parts of the house? G-d said, “They were witnesses in Egypt when I passed over the lintel and the two doorposts, saying, 'The children of Israel are my slaves', and not slaves to slaves, and I took them out of bondage. And this person went and acquired a master for himself? Let his ear be pierced in their presence.

A man of flesh and blood should not take another human being as his master, neither should he be a slave to himself. He is G-d's slave.
The Torah commanded us to keep laws and statutes which conceptually serve as a constant reminder of how abominable is conceit and how essential humility. In actual fact, the first commandment given to Israel when they ceased their bondage to mortal man was one intended to imbue them with humility; namely, the commandment to burn one's chametz [bread and other forms of leaven] before Pesach (Ex. 12:19; 13:7). Chametz, with its yeast which causes dough to expand, is a symbol of conceit which inflates a person's ego, enslaving and destroying him. The person enslaved by his pride and lust, the arrogant man who rebels against his task here on earth, rebels against the purpose of his and the world's having been created. He rebels against his Creator.
By contrast, someone who suppresses his evil impulse, overcoming his pride and lust, fulfills his task in the world.

This is man's whole purpose, the reason for his having been formed: to know G-d, cling to His attributes and fulfill His commandments. Within this very process, itself, comes self-effacement, subjugation of the evil impulse and a declaration: “The L-rd is G-d and there is no other – surely not myself – besides Him.”
Therefore, precisely during our season of freedom and national pride, when we celebrate liberation from the arrogant Egyptians and when exaltation would have been befitting and proper, G-d commanded base humility so Israel would remember that vis-a-vis G-d, they would always remain slaves, serving Him forever. As our sages said (Sifri, Shelach 115):

When G-d redeemed the seed of His beloved Abraham, He redeemed them not as sons but as slaves. Whenever He made a decree and they rejected it, He would say, “You are My slaves”. When they wnet out to the desert, He began to decree a few severe commandments and a few lighter ones... and Israel began to rebel. He said to them, “You are My slaves. I redeemed you on condition that I be able to decree and have you obey.”

Now, instead of being slaves of G-d, a title which is no disgrace, but the greatest praise a person can receive, we have become slaves of slaves.
Observe what our sages said (Sifri, Vezot HaBerachah, 357): “Slave of the L-rd” (Deut. 34:5): The Torah is not defaming Moses but praising him. We find that the first prophets were called slaves, as it says, “For the L-rd G-d does nothing without revealing His counsel unto His slaves the prophets” (Amos 3:7)

[Similarly we find in Rabbi Kahane's “Peirush haMaccabee” on Shemot, Chapter 2, regarding the Kohen:]
The Kohen is the one who serves and obeys, like a slave before his master. The Torah says: And Malchizedek, king of Salem, brought out bread and wine; and he was a Kohen of G-d, the Most High [which the Targum Onkelos renders: “and he served before G-d Most High”]. And he [Malchizedek] blessed him [Abram] saying: Blessed be Abram to G-d, the Most High, Possessor of Heaven and Earth (Genesis 14:18-19). Here we see that a Kohen of G-d is the person who begins with the understanding that Hashem is indeed the Possessor of heaven and earth – space, time, everything. And what exactly does the word koneh (“possessor”) really mean? – He is the Owner and the Master, because He has acquired everything by having created everything (as Rashi puts it: By having made them, He acquired them as His own). And this Kohen is a slave of G-d, and he is called by His Master’s Name because what the slave acquires his master acquires, because the slave is no more than his master’s hand. The Kohen in Israel is the one who has been sanctified to serve G-d in His Holy Temple, and only someone like that is worthy of placing Hashem’s Name on the nation, as the Torah says: And they [the Kohanim] will place My Name on the Children of Israel, and I will bless them (Numbers 6:27). The Torah also says: And you [Moses], draw close to yourself Aaron your brother and his sons with him, from among the Children of Israel, to minister to Me (Exodus 28:1).
...Aaron and the Kohanim were chosen to minister to Me, to be the slaves who would serve and obey Hashem in ministering to Him. They have been acquired as slaves to G-d the Most High, the Possessor of Heaven and Earth, and every day they testify to His omnipotence, and that He is Hashem, L-rd of Legions.

A slave of G-d is obligated to accept the yoke of his Master in heaven. He is lowly and belittles himself out of fear and reverence for his Master, the L-rd, and he esteems and praises Him as much as he can, as great, mighty and awesome. Precisely of all these reasons, precisely due to his fear of G-d, his fear of flesh and blood falls away. Any slave of G-d will never be a slave to a slave, i.e., to flesh and blood. Whoever truly stands in fear and trembling before the exclusive power and might of G-d will never fear mortal man, who comes from dust and returns to dust.
Such is the fear of G-d: Whoever stands in fear and trembling before G-d's majesty, astonished at His power and might, greatness and omnipotence, is at once seized with fear and reverence for his Maker and King; yet at the same time, all fear of flesh and blood leaves him, for of what importance is man?

Woe to us that, due to the curse of the exile, we have violated G-d's terrible prohibition which states, “The children of Israel are My slaves. They are My slaves because I brought them out of Egypt. I am the L-rd your G-d” (Lev. 25:55).
Due to our fear of the nations, we have become slaves to them of our own doing. We, thus, deserve the punishment of the slave whose ear is pierced:“He shall then serve his master forever” (Ex. 21:6).

Whoever takes a flesh-and-blood master because he fears him and relies on him and leans on his strength and kindness, denies the existence of G-d, the Supreme Master. Not only does he do this, but he profanes G-d's name (Torat Kohanim, Behar, 9): “The children of Israel are My slaves... I am the L-rd your G-d” This teaches that whenever Israel go into slavery here on earth, Scripture treats it as if G-d is going into slavery as well.” The simple meaning of this is that G-d took Israel out of Egyptian bondage to sanctify His name by showing the nations His power and might. Hence, when Israel once more become enslaved, where is G-d's power and where is His might? There is no greater Chilul Hashem than this. It is as though G-d is being enslaved by the nations, so to speak.
Now if it is so when a nation attacks Israel and enslaves them, what can we possibly say when a Jew fearfully enslaves himself to the non-Jew? Could any Chilul Hashem be greater? We must don sackcloth and ashes!

Our times constitute the beginning of the redemption and the footsteps of the Messiah. G-d in His kindness, in preparation for speedy redemption, presently demands of us Kiddush Hashem of the sort based on faith and trust in Him. Yet we, our children and our elders have sunk in the mire of exile, and have raised up on a miserable banner the fear and degradation of “It is forbidden to provoke the nations”. This theme, whose sorrowful conception and birth are in the exile, constitutes a humiliating affront to our people, and worse, a profanation of the great name of the Supreme King. If it suited the lowliness of the exile, when we were unwilling slaves to the nations, powerless to raise ourselves up to defend ourselves, how dare we bring that same disgraceful concept into the holy land, the land of G-d. While G-d has afforded us the greatest, most powerful miracles since the Hasmonean victories, we have remained that same exilic product, that same slave to the nations and slaves to slaves, with that same base spirit which led G-d to decree what He decreed against our ancestors in the desert.